Development of scales for the measurement of principles of design

• More than 100 items/indicators for principles of design are extracted from over 20 books written by practitioners.
• The items within the 6 principles are refined through 2 rounds of content analysis with 10 judges and 2 experts.
• Exploratory and confirmatory factor analyses are performed with more than 300 responses.
• The final items shown to have adequate convergent and discriminant validity.
• The field study shows that principles of design are better predictors of perceived ease of use.

Principles of design have been widely applied by practitioners such as photographers, artists, architects, designers, and others for many years. This paper examines whether the principles advocated by practitioners systematically and reliably influence perceived aesthetics and perceived ease of use constructs that are important for the evaluation of websites. To examine these relationships, the paper offers an operational definition, develops and validates a measurement tool for assessing the principles. To provide a comprehensive and broad definition of the principles, over 20 books written by practitioners were reviewed and more than 100 questionnaire items were extracted. These items were further refined through two rounds of content analysis using emergent and a priori coding with 10 judges and 2 experts. The remaining items from the two rounds of coding were examined using surveys. Exploratory and confirmatory factor analyses were performed. The results show that the items under 6 constructs have adequate convergent and discriminant validity. Lastly, a field study testing effects of the principles on perceived ease of use and aesthetics was conducted. The results show that principles of design predict perceived ease of use better than perceived aesthetics. Implications for practice and research are discussed.